- Wed Nov 18, 2009 10:47 am
#85343
Hello Forum members,
I am using MSP430F2618 with a XTAL of 1MHz connected to XT1 pins. The bus clock
(MCLK) is 250KHz while the aux clock (ACLK) is 1MHz. I am using ACLK to
different peripherals like UART, SPI, timer etc.
Is it possible that the timer execution will get affected as the MCLK and ACLK
differ very much - i.e. ACLK = four times MCLK? MCLK will be used to execute the
instructions while ACLK will drive the peripheral.
I observed similar while working with the timer ISRs. I am using
TI-MSP430FET(PIF) to debug my code having a timer ISR and updating the TBCCR0
and TBCCR1 registers. I observed a little difference in two register values when
I put breakpoint in ISR. Is the debugger playing any role for timer execution?
I have read the datasheet where it is stated that some cpu cycles will be used
to enter and exit the timer ISR. How is this affecting the timer counts?
Anyone having similar issues/observations.........?? Thanks in advance.
Mike
I am using MSP430F2618 with a XTAL of 1MHz connected to XT1 pins. The bus clock
(MCLK) is 250KHz while the aux clock (ACLK) is 1MHz. I am using ACLK to
different peripherals like UART, SPI, timer etc.
Is it possible that the timer execution will get affected as the MCLK and ACLK
differ very much - i.e. ACLK = four times MCLK? MCLK will be used to execute the
instructions while ACLK will drive the peripheral.
I observed similar while working with the timer ISRs. I am using
TI-MSP430FET(PIF) to debug my code having a timer ISR and updating the TBCCR0
and TBCCR1 registers. I observed a little difference in two register values when
I put breakpoint in ISR. Is the debugger playing any role for timer execution?
I have read the datasheet where it is stated that some cpu cycles will be used
to enter and exit the timer ISR. How is this affecting the timer counts?
Anyone having similar issues/observations.........?? Thanks in advance.
Mike